Functional Beads of Polyvinylpyrrolidone: Promising Support Materials for Solid‐Phase Synthesis

Abstract

AbstractSummary: The solubility properties of polyvinylpyrrolidone (PVP) make it an attractive material for several different polymer‐assisted synthesis applications. However, PVP lacks reactive groups necessary for attaching compounds to the polymer. Furthermore, the radical reactivity of 1‐vinylpyrrolidin‐2‐one (NVP) is different from most other monomers, which results in compositional drift during copolymerization. Therefore, introducing reactive groups into the polymer using this method is intricate. Smaller differences in radical reactivity are expected from monomers that are derivatives of NVP itself. Hence, such monomers provide a way of preparing PVP with adjustable properties. Four new monomers containing pendant double bonds, all derivatives of NVP, were synthesized and used in the preparation of a new type of hydrophilic polymer bead by aqueous suspension polymerization. We also found that undec‐10‐en‐1‐ol can be used as a comonomer for the introduction of functional groups. The lightly crosslinked beads contain hydroxyl groups at a functional loading of 0.28 mmol/g and swell extensively in a broad range of solvents. Their potential as support materials has previously been demonstrated in a five‐step solid‐phase synthesis of 5‐(2,4,6‐trimethoxy‐phenyl)‐cyclohexa‐1,3‐dienecarboxylic acid.Scanning electron microscopy image of dry beads from PVP‐[B]2.magnified imageScanning electron microscopy image of dry beads from PVP‐[B]2.